Switcheroo!
Current version: v1.3
✓ Switch your client to another server without changing the language or downloading additional patches.

✓ Saves your League of Legends install path so you don't have to select it every game

✓ Acts as a secondary launcher that starts LoL when it's done switching to the new region

✓ Supports all regions (Excluding China, Korea, Garena)
By downloading and/or using this application, you acknowledge and agree to abide by the terms.
NOTE: as with any other method of tampering with the game files, this can potentially break your game/launcher. USE AT YOUR OWN RISK
Download from lexwah.com
MEGA Mirror
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Recent changes:

v1.3 (17th January, 2015)
  • Support for Patch 5.1


v1.2 (16th December, 2014)
  • Added support for other languages (no Chinese or Japanese). Note: Users are responsible for making sure the language they select is the one they would like to keep when changing to a different region.
  • Program now automatically checks for updates


v1.1 (12th December, 2014)
  • Support for Patch 4.21
  • Support for switching between any region (Asian regions not included however)
  • Improved error detection


v1.0 (Some date that I don't remember)
  • Release! :D